The final answer for this question would be.....
8.8n^2+16n+0.1
Hope this helps!!!!

This can be considered as a very easy Question where you have to find the value of √85 and √86 upto 2 decimal places then we could find it easily.
Let's start!
Value of √85=9.21
Value of √86=9.27
Now it is obvious that 9.25 lies between √85 and √86.

What are rational no.?
Any pair of numbers which is in the form of p/q where p and q are integers and p and q are co-prime is called rational number.
Answer:
$390+0.07s=$544+0.05s Subtract $390 from each side.
0.07s=$154+0.05s Subtract 0.05s from each side.
0.02s=$154 Divide each side by 0.02.
s=$7700 Both plans pay the same when sales=$7700
ANSWER With sales greater than $7700, Chris is better off with Plan A.